Answer:

Step-by-step explanation:
Square of the monomial is 
To get the monomial we take square root
Lets take square root for each term

because square root of 4 is 2

2/2 is 1 so, its a^n
Required monomial is 
Answer:
A is the answer
Step-by-step explanation:
It's a larger number
-15+9=-6 --------> -6-12=-18
15 represents where he started, then he rises upward 9 and then gets to 6. Afterwards he goes down 12 and ends up at 18 which is 3 feet lower then where he originally started.<span />